eco-briefs

0
none | Boulder Weekly

INTERSEX FISH MAY ALLUDE TO A BIGGER PROBLEM

The recent discovery of intersex fish — males with eggs in their testes — in 60 percent of male black bass in North Carolina waterways adds to the growing accounts of intersex fish across the country.

Scientists at North Carolina State University conducted the as-yet unpublished research. They tested 20 rivers and streams throughout North Carolina for contaminants known to disrupt hormones finding 43 of the 135 contaminants they were looking for. The scientists are still analyzing differences in waterways and as such have not disclosed affected waterways.

Intersexuality in fish is caused by endocrine-disrupting chemicals including industrial chemicals, pesticides, excreted birth control and natural estrogens. When male fish develop female characteristics, reproductive problems can follow, threatening fish populations.

“Males guard the nest, create spawning nests for young and guard fertilized eggs. Males are crucial for hatching success and their male behavior could be altered by exposure to contaminants and the presence of the intersex condition,” Crystal Lee Pow, a Ph.D. student at North Carolina State University, one of the researchers on the project, said to EcoWatch.

Intersex fish have been previously documented across the country. A 2009 U.S. Geological Survey (USGS) study showed that of the smallmouth bass population in the Yampa River in Lay, Colo., 70 percent were intersex. Vicki Blazer, a USGS biologist, told the Washington Post the fish are “an indicator that something else is really wrong.”

“What are these things [pesticides] doing to the natural environment?” Blazer said. “If we find these things in wild organisms, there’s a good chance they’re also affecting people.”

— Nicole McNulty

STUDY LINKS INSECTICIDE TO BEE DECLINE FOR FIRST TIME

For the first time, a major study has found a direct correlation between neonicotinoids — the most widely used insecticides in the world — and declining global honeybee populations.

It’s a well-known fact that the world honeybee population has been dropping rapidly for more than a decade but the cause has proven difficult to pinpoint. Scientists have hypothesized many reasons for this phenomenon, but over the years, mounting evidence suggests a particular class of insecticides known as neonicotinoids, or neonics, are linked to widespread honeybee die-offs.

Still, no study had found a direct link.

That all changed this month with a major study from the U.K.-based Food and Environment Research Agency Published in the scientific journal Nature, the U.K. study analyzed the total cropped area of oilseed rape in England and Wales between 2000 and 2010, during which the total cropped area doubled while the use of seed coatings with neonics increased from less than one percent to 75 percent. Eight and a half percent of honeybee colonies observed were dead at the end of the study. The study highlighted the specific neonic imidacloprid as having a “positive relationship with honey bee colony losses.”

Imidacloprid is the same neonic that the Harvard School of Public Health (HSPH) declared in 2012 to be the likely cause of Colony Collapse Disorder (CCD) in honeybees.

The U.K. study coincides with results from a three-year U.S. Geological Survey that detected neonics in more than half of streams in the U.S. and Puerto Rico, with imidacloprid detected in 37 percent of samples, according to a press release.

— Nicole McNulty